Whilst Outlook, ActiveSync or Outlook Web App are recommended for a full client experience you may wish to configure IMAP access to your mailbox on Office 365.
For a comprehensive list of IMAP client setups click here.
If you're using your own client and are an experienced user, the server details are listed below:
Office 365 uses your email address in the form Firstname.Lastname@rhul.ac.uk as the username for a member of staff, and email@example.com as the username for a student.
When configuring your IMAP account, use settings similar to those shown below, substituting your email address in the E-mail Address and User Name fields.
To get to the screen below in Outlook go to File > Account Settings then select Account Settings... from the drop down, click on your email account and click Change...
Select More Settings and navigate to the Outgoing Server settings tab.
Select the checkbox My outgoing server (SMTP) requires authentication and ensure that Use same settings as my incoming mail server is selected.
Next, choose the Advanced tab and change the Incoming server (IMAP) port to 993 using SSL as the type of encryption. Change the Outgoing server (SMTP) port to 587 using TLS as the type of encryption, then press OK.
After selecting the option to Test Account Settings you should now have successfully set up Outlook to communicate with Office 365.
For comprehensive help and troubleshooting of Office 365 visit Microsoft's Outlook help by clicking here.